Shell Programming and Scripting

Hi all,

Thanks in advance

I want to do simple calculations..using files

for example:

i have 2 files called anish.txt and kumar.txt

anish.txt contains value 10 and kumar.txt contains value 5

anish.txt - kumar.txt = 5

i want to display like this

how to do this process , and dont think as home work and all this small process helpful to me to move next step in my script.

Thanks and Regards
Anish kumar.V

one entry per file?

--ahamed

In shell:

Code:

read VAR1 < file1.txt
read VAR2 < file2.txt
expr "${VAR1}" "+" "${VAR2}"

There's better ways than 'expr' in some shells, but I don't know what your system and shell is.

Code:

 echo 10 >file1
 echo 5 >file2
 echo $(( $(<file1) - $(<file2) ))

$(( )) allows integer math: addition, subtraction, multiplication, division, % (modulo)

Code:

awk 'NR==FNR{a=$0;next} {b=$0; print a-b}' anish.txt kumar.txt

--ahamed

Hi all,

Thanks a lot for your immediate response.



and ahamed

AWK is better for me and previously i made some steps using AWK and i need your help


i got an idea to finish this script but for that i need your help is it possoble to do like this


Example:

/var/tmp/v1 file contians anish.txt this name

/var/tmp/v2 file contians kumar.txt this name

Code:

awk 'NR==FNR{a=$0;next} {b=$0; print a-b}' /var/tmpanish.txt /var/tmp/kumar.txt

i know this command wont work and is that any alternate way ? to get this 2 values from the file

Code:

awk 'NR==FNR{a=$0;next} {b=$0; print a-b}' $(</var/tmpanish.txt) $(</var/tmp/kumar.txt)

thanks to Jim's post

--ahamed